This invention relates to a multiple slot writing instrument and more particularly a writing instrument which comprises: a plurality of slots for holding writing implements such as colored leads for color pencils or ballpoint pens, the slots being formed radially in the inner wall of a cylindrical body; a guide tube mounted coaxially within the cylindrical body and having an opening which can be aligned with any one of the slots; and a chuck fitted at the front end of the guide tube for clamping the writing implement; whereby a selected writing implement in the slot is allowed to drop by gravity into the guide tube through the opening and then is clamped by the chuck, thus permitting the user to write.
The terminology "writing implement" intends to mean colored leads for color pencils and writing elements of ball point pens.
The conventional writing instrument of this kind is known to have a construction such that the opening of the guide tube is made to directly communicate with the slots in turn--which are formed in the inner wall of the cylindrical body--by rotating the guide tube (as in the Japanese Utility Model Publication No. 17934/1976). However, this kind of writing instrument has a disadvantage that during the process of rotating the guide tube to align the opening with a desired slot, other writing implement (i.e., leads) contained in any one of the slots located before the selected one, may drop into the guide tube through the opening, resulting in malfunctions.
To overcome the above-mentioned drawback, various proposals have been made. In one proposal (Japanese Utility Model Publication No. 34188/1974), the writing instrument is provided with a support rod and a release means. The support rod is installed at the upper portion of each slot to press the upper end of the writing implement against the inner wall of the cylindrical body. The release means which is provided to and integrally formed with the upper portion of the guide tube releases the support rod to drop the selected writing implement.
In another proposal (Japanese Utility Model Publication No. 34190/1974), a magnetic pipe which is fitted to the upper end of the writing implement contained in a corresponding slot is attracted by a permanent magnet. In releasing the selected writing implement from the permanent magnet, a ram rod provided to and formed integral with the upper portion of the guide tube is inserted into a through-hole cut through the permanent magnet to push the top of the magnetic pipe away from the permanent magnet.
These constructions, however, are too complicated and therefore stable operation cannot be obtained.